“They lied to me. At first they said the attackers were under investigation. Later they said they didn't know who any of them were."

A South Korean student whose finger was chopped off in a brutal attack has spoken of his frustration with a police investigation into the incident.

Mr Chang, who is keeping his identity concealed, and a friend were attacked by a group of teenagers while walking through Box Hill Gardens in Melbourne at night in September.

The attackers severed his left little finger and broke his arm. Mr Chang, who has worked as a designer and is left-handed, fears the injury will affect his ability to work in future.

“I feel so embarrassed and humiliated,” the TAFE Box Hill Institute student, 33, said. “I don't want to go outside alone. I haven't even told my family about what happened. They don't know.”

Over the past two months two other Korean nationals, a 33-year-old Sydney man and a 27-year-old man from Brisbane, have also been attacked, fuelling outrage in South Korea, with media reports questioning whether Australia is a safe place to visit.

Two weeks ago, French woman Fanny Desaintjores was threatened by passengers on a Melbourne bus for singing French songs. One man said “speak English or die”, while another commuter shouted: “I'll f---ing boxcutter you right now, dog.”

Victoria Police is continuing its investigations into the assault against Mr Chang after the South Korean government requested they conduct a "more thorough and fair investigation", capture the perpetrators and compensate the victim.

The Foreign Ministry of South Korea also demanded Australia "come up with measures to prevent future incidents", the Korean broadcaster KBS reported.

Mr Chang, from Seoul, still believes Australia is a “safe and good country”, acknowledging every country has its share of offenders. But he said he was “unhappy” about the ongoing police investigation.

A spokesman from the Korean Consulate in Melbourne told Fairfax Media they formally requested Victoria Police to “carry out a thorough investigation that will also eliminate perceptions of unfairness and inadequacy from the victim and Korean public”.

Mr Chang had declared he was told by police he was responsible for the brutal attack because he “was in the wrong place at the wrong hours”, sparking alarm in Korea.

But the spokesman said that while police eventually apologised for the remark to Mr Chang, he may have “misunderstood the intention behind it, taken in the wrong way due to cultural differences”.

The Korean newspaper Chosun Ilbo reported Mr Chang was approached by a group of teenagers who asked for a cigarette. When he refused, they assaulted him while shouting the words "f---ing Chinese".

Mr Chang blacked out during the attack and was taken to hospital, where his little finger was reattached.

Victoria Police has told Fairfax Media a 14-year-old boy from Doncaster, Melbourne, was charged the day after the assault.

Mr Chang is now seeking compensation through the Victims of Crime Assistance Tribunal.

The Department of Foreign Affairs and Trade on Monday night said it was aware of the media reports of assaults against Korean nationals in Melbourne, Sydney and Brisbane.

"The Australian Government and Australian state and territory police forces take very seriously any allegations of racially-motivated crime," the spokeswoman said.

"Regrettably, crimes occur in Australia as they do in all countries, and it is important to be very careful in reaching conclusions that they are racially motivated."